Abstract: For finite cyclic groups G of even order, the image of unoriented G bordism in Z/2Z bordism and the kernel of the extension homomorphism from Z/2Z to G bordism depend only on whether or not the order of G is divisible by four. If so, then these sets are equal and are equal to the image of circle bordism in Z/2Z bordism and the kernel of extension to circle bordism. If not, then extension is a monomorphism and restriction is an epimorphism.